For applications such as standards conversion and generation of slow and fast motion in film, television and other video productions, images in a sequence of images may be simply repeated or dropped to achieve a desired sampling rate. Such a technique, however, generally produces unwanted visible artifacts such as jerky motion. Analysis of motion in a sequence of images is commonly used to improve interpolation of the sequence of images.
Motion analysis generally is performed by determining a set of motion parameters that describe motion of pixels between a first image and a second image. For example, the motion parameters may describe forward motion of pixels from the first image to the second image, and/or backward motion of pixels from the second image to the first image. The motion parameters may be defined at a time associated with either or both of the first and second images or at a time between the first and second images. These motion parameters are then used to warp the first and second images to obtain an interpolated image between the first and second images. This process generally is called motion compensated interpolation.